Steel Buildings in Europe

Part 2: Concept Design 2 - 72 Figure 6.6 Typical fixing details to concrete slabs 6.8.2 Glazing systems Many steel structures have glazed facades. T here a re a large num ber of different system s, and the m anufacturer of the system should be consulted when specifying the system , and particular ly the fixings to the steel fram e. In many cases the f ixings will be at th e corners of glazed pan els, and the panels themselves will have some form of gasket on the joints between panels. A number of i mportant issues need to be addressed, notably the need to m ake provision for adjustment in the connections, because the tolerances on the steel frame and the glazing panels are generall y different. Movement due to thermal effects m ay be s ignificant, and this will have to be acco mmodated in th e support system. 6.8.3 Curtain walling Curtain walling includes:  Metal panels (generally steel or aluminium)  Precast concrete panels  Stone cladding. Curtain walling may be able to support their own weight and the applied loads without add itional s tructural system s. This type of panel is generally hung, (supported at the top of the panel) or supported at their base from the floor. Generally, each panel s ystem will have a proprie tary fixing detail th at allows for m ovement and adjustm ent in three directions, in orde r to ov ercome the difference in tolerances of the fra me and cladding panels. The connections can be substantial, and provision m ay be require to conceal the connections in a raised floor or ceiling zone. The slab design m ay need review in order to accommodate the local connection forces. It is also comm on that fixing s will be required to the outside edge of a floor, which is usually achieved by a dovetail channel cast into the edge of the slab. Cladding may require a dditional s tructural support – gen erally in the form of mullions which m ay ext end vertically ove r a number of floor s, possibly with intermediate horizonta l m embers (tran soms). Vertical or horizontal m etal sheeting is often supported in this way. The connections need careful consideration, to allow f or adjustm ent in three dir ections, and to allow f or movement whilst carrying lateral loads to the floors.